Most of Faerûn uses the Calendar of Harptos, named after the long-dead wizard who invented it. Few bother to refer to Harptos by name, since the calendar is the only calendar they know.

Each year of 365 days is divided into 12 months of 30 days, and each month is divided into three tendays. Five special days fall between the months. These annual holidays mark the seasons or the changing of the seasons. The months of Faerûn roughly correspond to the months of the Gregorian calendar.

1 - Hammer (Deepwinter)

Midwinter

2 - Alturiak (the Claw of Winter or the Claws of the Cold)3 - Ches (the Claw of Sunsets)4 - Tarsakh (the Claw of Storms)